/*------------------------------------------------------------------------------
* rcvraw.c : receiver raw data functions
*
*          Copyright (C) 2009-2018 by T.TAKASU, All rights reserved.
*          Copyright (C) 2014 by T.SUZUKI, All rights reserved.
*
* references :
*     [1] IS-GPS-200D, Navstar GPS Space Segment/Navigation User Interfaces,
*         7 March, 2006
*     [2] Global navigation satellite system GLONASS interface control document
*         navigation radiosignal in bands L1,L2 (version 5.1), 2008
*     [3] BeiDou satellite navigation system signal in space interface control
*         document open service signal (version 2.0), December 2013
*     [4] Quasi-Zenith Satellite System Navigation Service Interface
*         Specification for QZSS (IS-QZSS) V.1.5, March 27, 2014
*     [5] European GNSS (Galileo) Open Service Signal In Space Interface Control
*         Document, Issue 1.2, November 2015
*
* version : $Revision: 1.1 $ $Date: 2008/07/17 21:48:06 $
* history : 2009/04/10 1.0  new
*           2009/06/02 1.1  support glonass
*           2010/07/31 1.2  support eph_t struct change
*           2010/12/06 1.3  add almanac decoding, support of GW10
*                           change api decode_frame()
*           2013/04/11 1.4  fix bug on decode fit interval
*           2014/01/31 1.5  fix bug on decode fit interval
*           2014/06/22 1.6  add api decode_glostr()
*           2014/06/22 1.7  add api decode_bds_d1(), decode_bds_d2()
*           2014/08/14 1.8  add test_glostr()
*                           add support input format rt17
*           2014/08/31 1.9  suppress warning
*           2014/11/07 1.10 support qzss navigation subframes
*           2018/01/29 1.11 add api decode_gal_inav() for galileo I/NAV
*                           improve struct initialization in init_raw()
*-----------------------------------------------------------------------------*/
#include "rtklib.h"
#include <stdint.h>

#define P2_34       5.820766091346740E-11 /* 2^-34 */
#define P2_46       1.421085471520200E-14 /* 2^-46 */
#define P2_59       1.734723475976810E-18 /* 2^-59 */
#define P2_66       1.355252715606881E-20 /* 2^-66 for BeiDou ephemeris */

/* get two component bits ----------------------------------------------------*/
static unsigned int getbitu2(const unsigned char *buff, int p1, int l1, int p2,
                             int l2)
{
    return (getbitu(buff,p1,l1)<<l2)+getbitu(buff,p2,l2);
}
static int getbits2(const unsigned char *buff, int p1, int l1, int p2, int l2)
{
    if (getbitu(buff,p1,1))
        return (int)((getbits(buff,p1,l1)<<l2)+getbitu(buff,p2,l2));
    else
        return (int)getbitu2(buff,p1,l1,p2,l2);
}
/* get three component bits --------------------------------------------------*/
static unsigned int getbitu3(const unsigned char *buff, int p1, int l1, int p2,
                             int l2, int p3, int l3)
{
    return (getbitu(buff,p1,l1)<<(l2+l3))+(getbitu(buff,p2,l2)<<l3)+
            getbitu(buff,p3,l3);
}
static int getbits3(const unsigned char *buff, int p1, int l1, int p2, int l2,
                    int p3, int l3)
{
    if (getbitu(buff,p1,1))
        return (int)((getbits(buff,p1,l1)<<(l2+l3))+
                   (getbitu(buff,p2,l2)<<l3)+getbitu(buff,p3,l3));
    else
        return (int)getbitu3(buff,p1,l1,p2,l2,p3,l3);
}
/* merge two components ------------------------------------------------------*/
static unsigned int merge_two_u(unsigned int a, unsigned int b, int n)
{
    return (a<<n)+b;
}
static int merge_two_s(int a, unsigned int b, int n)
{
    return (int)((a<<n)+b);
}
/* get sign-magnitude bits ---------------------------------------------------*/
static double getbitg(const unsigned char *buff, int pos, int len)
{
    double value=getbitu(buff,pos+1,len-1);
    return getbitu(buff,pos,1)?-value:value;
}
/* decode Galileo I/NAV ephemeris ----------------------------------------------
* decode Galileo I/NAV (ref [5] 4.3)
* args   : unsigned char *buff I Galileo I/NAV subframe bits
*                                  buff[ 0-15]: I/NAV word type 0 (128 bit)
*                                  buff[16-31]: I/NAV word type 1
*                                  buff[32-47]: I/NAV word type 2
*                                  buff[48-63]: I/NAV word type 3
*                                  buff[64-79]: I/NAV word type 4
*                                  buff[80-95]: I/NAV word type 5
*          eph_t    *eph    IO  ephemeris structure
* return : status (1:ok,0:error)
*-----------------------------------------------------------------------------*/
extern int decode_gal_inav(const unsigned char *buff, eph_t *eph)
{
    double tow,toc,tt,sqrtA;
    int i,time_f,week,svid,e5b_hs,e1b_hs,e5b_dvs,e1b_dvs,type[6],iod_nav[4];
    
    i=0; /* word type 0 */
    type[0]    =getbitu(buff,i, 6);              i+= 6;
    time_f     =getbitu(buff,i, 2);              i+= 2+88;
    week       =getbitu(buff,i,12);              i+=12; /* gst-week */
    tow        =getbitu(buff,i,20);
    
    i=128; /* word type 1 */
    type[1]    =getbitu(buff,i, 6);              i+= 6;
    iod_nav[0] =getbitu(buff,i,10);              i+=10;
    eph->toes  =getbitu(buff,i,14)*60.0;         i+=14;
    eph->M0    =getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->e     =getbitu(buff,i,32)*P2_33;        i+=32;
    sqrtA      =getbitu(buff,i,32)*P2_19;
    
    i=128*2; /* word type 2 */
    type[2]    =getbitu(buff,i, 6);              i+= 6;
    iod_nav[1] =getbitu(buff,i,10);              i+=10;
    eph->OMG0  =getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->i0    =getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->omg   =getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->idot  =getbits(buff,i,14)*P2_43*SC2RAD;
    
    i=128*3; /* word type 3 */
    type[3]    =getbitu(buff,i, 6);              i+= 6;
    iod_nav[2] =getbitu(buff,i,10);              i+=10;
    eph->OMGd  =getbits(buff,i,24)*P2_43*SC2RAD; i+=24;
    eph->deln  =getbits(buff,i,16)*P2_43*SC2RAD; i+=16;
    eph->cuc   =getbits(buff,i,16)*P2_29;        i+=16;
    eph->cus   =getbits(buff,i,16)*P2_29;        i+=16;
    eph->crc   =getbits(buff,i,16)*P2_5;         i+=16;
    eph->crs   =getbits(buff,i,16)*P2_5;         i+=16;
    eph->sva   =getbitu(buff,i, 8);
    
    i=128*4; /* word type 4 */
    type[4]    =getbitu(buff,i, 6);              i+= 6;
    iod_nav[3] =getbitu(buff,i,10);              i+=10;
    svid       =getbitu(buff,i, 6);              i+= 6;
    eph->cic   =getbits(buff,i,16)*P2_29;        i+=16;
    eph->cis   =getbits(buff,i,16)*P2_29;        i+=16;
    toc        =getbitu(buff,i,14)*60.0;         i+=14;
    eph->f0    =getbits(buff,i,31)*P2_34;        i+=31;
    eph->f1    =getbits(buff,i,21)*P2_46;        i+=21;
    eph->f2    =getbits(buff,i, 6)*P2_59;
    
    i=128*5; /* word type 5 */
    type[5]    =getbitu(buff,i, 6);              i+= 6+41;
    eph->tgd[0]=getbits(buff,i,10)*P2_32;        i+=10; /* BGD E5a/E1 */
    eph->tgd[1]=getbits(buff,i,10)*P2_32;        i+=10; /* BGD E5b/E1 */
    e5b_hs     =getbitu(buff,i, 2);              i+= 2;
    e1b_hs     =getbitu(buff,i, 2);              i+= 2;
    e5b_dvs    =getbitu(buff,i, 1);              i+= 1;
    e1b_dvs    =getbitu(buff,i, 1);
    
    /* test word types */
    if (type[0]!=0||type[1]!=1||type[2]!=2||type[3]!=3||type[4]!=4) {
        trace(3,"decode_gal_inav error: type=%d %d %d %d %d\n",type[0],type[1],
              type[2],type[3],type[4]);
        return 0;
    }
    /* test word type 0 time field */
    if (time_f!=2) {
        trace(3,"decode_gal_inav error: word0-time=%d\n",time_f);
        return 0;
    }
    /* test consistency of iod_nav */
    if (iod_nav[0]!=iod_nav[1]||iod_nav[0]!=iod_nav[2]||iod_nav[0]!=iod_nav[3]) {
        trace(3,"decode_gal_inav error: ionav=%d %d %d %d\n",iod_nav[0],
              iod_nav[1],iod_nav[2],iod_nav[3]);
        return 0;
    }
    if (!(eph->sat=satno(SYS_GAL,svid))) {
        trace(2,"decode_gal_inav svid error: svid=%d\n",svid);
        return 0;
    }
    eph->A=sqrtA*sqrtA;
    eph->iode=eph->iodc=iod_nav[0];
    eph->svh=(e5b_hs<<7)|(e5b_dvs<<6)|(e1b_hs<<1)|e1b_dvs;
    eph->ttr=gst2time(week,tow);
    tt=timediff(gst2time(week,eph->toes),eph->ttr); /* week complient to toe */
    if      (tt> 302400.0) week--;
    else if (tt<-302400.0) week++;
    eph->toe=gst2time(week,eph->toes);
    eph->toc=gst2time(week,toc);
    eph->week=week+1024; /* gal-week = gst-week + 1024 */
    eph->code=1;         /* data source = I/NAV E1B */
    
    return 1;
}
/* decode BeiDou D1 ephemeris --------------------------------------------------
* decode BeiDou D1 ephemeris (IGSO/MEO satellites) (ref [3] 5.2)
* args   : unsigned char *buff I beidou D1 subframe bits
*                                  buff[ 0- 37]: subframe 1 (300 bits)
*                                  buff[38- 75]: subframe 2
*                                  buff[76-113]: subframe 3
*          eph_t    *eph    IO  ephemeris structure
* return : status (1:ok,0:error)
*-----------------------------------------------------------------------------*/
extern int decode_bds_d1(const unsigned char *buff, eph_t *eph)
{
    double toc_bds,sqrtA;
    unsigned int toe1,toe2,sow1,sow2,sow3;
    int i,frn1,frn2,frn3;
    
    trace(3,"decode_bds_d1:\n");
    
    i=8*38*0; /* subframe 1 */
    frn1       =getbitu (buff,i+ 15, 3);
    sow1       =getbitu2(buff,i+ 18, 8,i+30,12);
    eph->svh   =getbitu (buff,i+ 42, 1); /* SatH1 */
    eph->iodc  =getbitu (buff,i+ 43, 5); /* AODC */
    eph->sva   =getbitu (buff,i+ 48, 4);
    eph->week  =getbitu (buff,i+ 60,13); /* week in BDT */
    toc_bds    =getbitu2(buff,i+ 73, 9,i+ 90, 8)*8.0;
    eph->tgd[0]=getbits (buff,i+ 98,10)*0.1*1E-9;
    eph->tgd[1]=getbits2(buff,i+108, 4,i+120, 6)*0.1*1E-9;
    eph->f2    =getbits (buff,i+214,11)*P2_66;
    eph->f0    =getbits2(buff,i+225, 7,i+240,17)*P2_33;
    eph->f1    =getbits2(buff,i+257, 5,i+270,17)*P2_50;
    eph->iode  =getbitu (buff,i+287, 5); /* AODE */
    
    i=8*38*1; /* subframe 2 */
    frn2       =getbitu (buff,i+ 15, 3);
    sow2       =getbitu2(buff,i+ 18, 8,i+30,12);
    eph->deln  =getbits2(buff,i+ 42,10,i+ 60, 6)*P2_43*SC2RAD;
    eph->cuc   =getbits2(buff,i+ 66,16,i+ 90, 2)*P2_31;
    eph->M0    =getbits2(buff,i+ 92,20,i+120,12)*P2_31*SC2RAD;
    eph->e     =getbitu2(buff,i+132,10,i+150,22)*P2_33;
    eph->cus   =getbits (buff,i+180,18)*P2_31;
    eph->crc   =getbits2(buff,i+198, 4,i+210,14)*P2_6;
    eph->crs   =getbits2(buff,i+224, 8,i+240,10)*P2_6;
    sqrtA      =getbitu2(buff,i+250,12,i+270,20)*P2_19;
    toe1       =getbitu (buff,i+290, 2); /* TOE 2-MSB */
    eph->A     =sqrtA*sqrtA;
    
    i=8*38*2; /* subframe 3 */
    frn3       =getbitu (buff,i+ 15, 3);
    sow3       =getbitu2(buff,i+ 18, 8,i+30,12);
    toe2       =getbitu2(buff,i+ 42,10,i+ 60, 5); /* TOE 5-LSB */
    eph->i0    =getbits2(buff,i+ 65,17,i+ 90,15)*P2_31*SC2RAD;
    eph->cic   =getbits2(buff,i+105, 7,i+120,11)*P2_31;
    eph->OMGd  =getbits2(buff,i+131,11,i+150,13)*P2_43*SC2RAD;
    eph->cis   =getbits2(buff,i+163, 9,i+180, 9)*P2_31;
    eph->idot  =getbits2(buff,i+189,13,i+210, 1)*P2_43*SC2RAD;
    eph->OMG0  =getbits2(buff,i+211,21,i+240,11)*P2_31*SC2RAD;
    eph->omg   =getbits2(buff,i+251,11,i+270,21)*P2_31*SC2RAD;
    eph->toes  =merge_two_u(toe1,toe2,15)*8.0;
    
    /* check consistency of subframe numbers, sows and toe/toc */
    if (frn1!=1||frn2!=2||frn3!=3) {
        trace(3,"decode_bds_d1 error: frn=%d %d %d\n",frn1,frn2,frn3);
        return 0;
    }
    if (sow2!=sow1+6||sow3!=sow2+6) {
        trace(3,"decode_bds_d1 error: sow=%d %d %d\n",sow1,sow2,sow3);
        return 0;
    }
    if (toc_bds!=eph->toes) {
        trace(3,"decode_bds_d1 error: toe=%.0f toc=%.0f\n",eph->toes,toc_bds);
        return 0;
    }
    eph->ttr=bdt2gpst(bdt2time(eph->week,sow1));      /* bdt -> gpst */
    if      (eph->toes>sow1+302400.0) eph->week++;
    else if (eph->toes<sow1-302400.0) eph->week--;
    eph->toe=bdt2gpst(bdt2time(eph->week,eph->toes)); /* bdt -> gpst */
    eph->toc=bdt2gpst(bdt2time(eph->week,toc_bds));   /* bdt -> gpst */
    return 1;
}
/* decode BeiDou D2 ephemeris --------------------------------------------------
* decode BeiDou D2 ephemeris (GEO satellites) (ref [3] 5.3)
* args   : unsigned char *buff I beidou D2 subframe 1 page bits
*                                  buff[  0- 37]: page 1 (300 bits)
*                                  buff[ 38- 75]: page 2
*                                  ...
*                                  buff[342-379]: page 10
*          eph_t    *eph    IO  ephemeris structure
* return : status (1:ok,0:error)
*-----------------------------------------------------------------------------*/
extern int decode_bds_d2(const unsigned char *buff, eph_t *eph)
{
    double toc_bds,sqrtA;
    unsigned int f1p4,cucp5,ep6,cicp7,i0p8,OMGdp9,omgp10;
    unsigned int sow1,sow3,sow4,sow5,sow6,sow7,sow8,sow9,sow10;
    int i,f1p3,cucp4,ep5,cicp6,i0p7,OMGdp8,omgp9;
    int pgn1,pgn3,pgn4,pgn5,pgn6,pgn7,pgn8,pgn9,pgn10;
    
    trace(3,"decode_bds_d2:\n");
    
    i=8*38*0; /* page 1 */
    pgn1       =getbitu (buff,i+ 42, 4);
    sow1       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    eph->svh   =getbitu (buff,i+ 46, 1); /* SatH1 */
    eph->iodc  =getbitu (buff,i+ 47, 5); /* AODC */
    eph->sva   =getbitu (buff,i+ 60, 4);
    eph->week  =getbitu (buff,i+ 64,13); /* week in BDT */
    toc_bds    =getbitu2(buff,i+ 77, 5,i+ 90,12)*8.0;
    eph->tgd[0]=getbits (buff,i+102,10)*0.1*1E-9;
    eph->tgd[1]=getbits (buff,i+120,10)*0.1*1E-9;
    
    i=8*38*2; /* page 3 */
    pgn3       =getbitu (buff,i+ 42, 4);
    sow3       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    eph->f0    =getbits2(buff,i+100,12,i+120,12)*P2_33;
    f1p3       =getbits (buff,i+132,4);
    
    i=8*38*3; /* page 4 */
    pgn4       =getbitu (buff,i+ 42, 4);
    sow4       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    f1p4       =getbitu2(buff,i+ 46, 6,i+ 60,12);
    eph->f2    =getbits2(buff,i+ 72,10,i+ 90, 1)*P2_66;
    eph->iode  =getbitu (buff,i+ 91, 5); /* AODE */
    eph->deln  =getbits (buff,i+ 96,16)*P2_43*SC2RAD;
    cucp4      =getbits (buff,i+120,14);
    
    i=8*38*4; /* page 5 */
    pgn5       =getbitu (buff,i+ 42, 4);
    sow5       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    cucp5      =getbitu (buff,i+ 46, 4);
    eph->M0    =getbits3(buff,i+ 50, 2,i+ 60,22,i+ 90, 8)*P2_31*SC2RAD;
    eph->cus   =getbits2(buff,i+ 98,14,i+120, 4)*P2_31;
    ep5        =getbits (buff,i+124,10);
    
    i=8*38*5; /* page 6 */
    pgn6       =getbitu (buff,i+ 42, 4);
    sow6       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    ep6        =getbitu2(buff,i+ 46, 6,i+ 60,16);
    sqrtA      =getbitu3(buff,i+ 76, 6,i+ 90,22,i+120,4)*P2_19;
    cicp6      =getbits (buff,i+124,10);
    eph->A     =sqrtA*sqrtA;
    
    i=8*38*6; /* page 7 */
    pgn7       =getbitu (buff,i+ 42, 4);
    sow7       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    cicp7      =getbitu2(buff,i+ 46, 6,i+ 60, 2);
    eph->cis   =getbits (buff,i+ 62,18)*P2_31;
    eph->toes  =getbitu2(buff,i+ 80, 2,i+ 90,15)*8.0;
    i0p7       =getbits2(buff,i+105, 7,i+120,14);
    
    i=8*38*7; /* page 8 */
    pgn8       =getbitu (buff,i+ 42, 4);
    sow8       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    i0p8       =getbitu2(buff,i+ 46, 6,i+ 60, 5);
    eph->crc   =getbits2(buff,i+ 65,17,i+ 90, 1)*P2_6;
    eph->crs   =getbits (buff,i+ 91,18)*P2_6;
    OMGdp8     =getbits2(buff,i+109, 3,i+120,16);
    
    i=8*38*8; /* page 9 */
    pgn9       =getbitu (buff,i+ 42, 4);
    sow9       =getbitu2(buff,i+ 18, 8,i+ 30,12);
    OMGdp9     =getbitu (buff,i+ 46, 5);
    eph->OMG0  =getbits3(buff,i+ 51, 1,i+ 60,22,i+ 90, 9)*P2_31*SC2RAD;
    omgp9      =getbits2(buff,i+ 99,13,i+120,14);
    
    i=8*38*9; /* page 10 */
    pgn10      =getbitu (buff,i+ 42, 4);
    sow10      =getbitu2(buff,i+ 18, 8,i+ 30,12);
    omgp10     =getbitu (buff,i+ 46, 5);
    eph->idot  =getbits2(buff,i+ 51, 1,i+ 60,13)*P2_43*SC2RAD;
    
    /* check consistency of page numbers, sows and toe/toc */
    if (pgn1!=1||pgn3!=3||pgn4!=4||pgn5!=5||pgn6!=6||pgn7!=7||pgn8!=8||pgn9!=9||
        pgn10!=10) {
        trace(3,"decode_bds_d2 error: pgn=%d %d %d %d %d %d %d %d %d\n",
              pgn1,pgn3,pgn4,pgn5,pgn6,pgn7,pgn8,pgn9,pgn10);
        return 0;
    }
    if (sow3!=sow1+6||sow4!=sow3+3||sow5!=sow4+3||sow6!=sow5+3||
        sow7!=sow6+3||sow8!=sow7+3||sow9!=sow8+3||sow10!=sow9+3) {
        trace(3,"decode_bds_d2 error: sow=%d %d %d %d %d %d %d %d %d\n",
              sow1,sow3,sow4,sow5,sow6,sow7,sow8,sow9,sow10);
        return 0;
    }
    if (toc_bds!=eph->toes) {
        trace(3,"decode_bds_d2 error: toe=%.0f toc=%.0f\n",eph->toes,toc_bds);
        return 0;
    }
    eph->f1  =merge_two_s(f1p3  ,f1p4  ,18)*P2_50;
    eph->cuc =merge_two_s(cucp4 ,cucp5 , 4)*P2_31;
    eph->e   =merge_two_s(ep5   ,ep6   ,22)*P2_33;
    eph->cic =merge_two_s(cicp6 ,cicp7 , 8)*P2_31;
    eph->i0  =merge_two_s(i0p7  ,i0p8  ,11)*P2_31*SC2RAD;
    eph->OMGd=merge_two_s(OMGdp8,OMGdp9, 5)*P2_43*SC2RAD;
    eph->omg =merge_two_s(omgp9 ,omgp10, 5)*P2_31*SC2RAD;
    
    eph->ttr=bdt2gpst(bdt2time(eph->week,sow1));      /* bdt -> gpst */
    if      (eph->toes>sow1+302400.0) eph->week++;
    else if (eph->toes<sow1-302400.0) eph->week--;
    eph->toe=bdt2gpst(bdt2time(eph->week,eph->toes)); /* bdt -> gpst */
    eph->toc=bdt2gpst(bdt2time(eph->week,toc_bds));   /* bdt -> gpst */
    return 1;
}
/* test hamming code of glonass ephemeris string -------------------------------
* test hamming code of glonass ephemeris string (ref [2] 4.7)
* args   : unsigned char *buff I glonass navigation data string bits in frame
*                                with hamming
*                                  buff[ 0]: string bit 85-78
*                                  buff[ 1]: string bit 77-70
*                                  ...
*                                  buff[10]: string bit  5- 1 (0 padded)
* return : status (1:ok,0:error)
*-----------------------------------------------------------------------------*/
extern int test_glostr(const unsigned char *buff)
{
    static const unsigned char xor_8bit[256]={ /* xor of 8 bits */
        0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
        1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
        1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
        0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
        1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
        0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
        0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
        1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0
    };
    static const unsigned char mask_hamming[][12]={ /* mask of hamming codes */
        {0x55,0x55,0x5A,0xAA,0xAA,0xAA,0xB5,0x55,0x6A,0xD8,0x08},
        {0x66,0x66,0x6C,0xCC,0xCC,0xCC,0xD9,0x99,0xB3,0x68,0x10},
        {0x87,0x87,0x8F,0x0F,0x0F,0x0F,0x1E,0x1E,0x3C,0x70,0x20},
        {0x07,0xF8,0x0F,0xF0,0x0F,0xF0,0x1F,0xE0,0x3F,0x80,0x40},
        {0xF8,0x00,0x0F,0xFF,0xF0,0x00,0x1F,0xFF,0xC0,0x00,0x80},
        {0x00,0x00,0x0F,0xFF,0xFF,0xFF,0xE0,0x00,0x00,0x01,0x00},
        {0xFF,0xFF,0xF0,0x00,0x00,0x00,0x00,0x00,0x00,0x02,0x00},
        {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xF8}
    };
    unsigned char cs;
    int i,j,n=0;
    
    for (i=0;i<8;i++) {
        for (j=0,cs=0;j<11;j++) {
            cs^=xor_8bit[buff[j]&mask_hamming[i][j]];
        }
        if (cs) n++;
    }
    return n==0||(n==2&&cs);
}
/* decode glonass ephemeris strings --------------------------------------------
* decode glonass ephemeris string (ref [2])
* args   : unsigned char *buff I glonass navigation data string bits in frames
*                                (without hamming and time mark)
*                                  buff[ 0- 9]: string #1 (77 bits)
*                                  buff[10-19]: string #2
*                                  buff[20-29]: string #3
*                                  buff[30-39]: string #4
*          geph_t *geph  IO     glonass ephemeris message
* return : status (1:ok,0:error)
* notes  : geph->tof should be set to frame time witin 1/2 day before calling
*          geph->frq is set to 0
*-----------------------------------------------------------------------------*/
extern int decode_glostr(const unsigned char *buff, geph_t *geph)
{
    double tow,tod,tof,toe;
    int P,P1,P2,P3,P4,tk_h,tk_m,tk_s,tb,ln,NT,slot,M,week;
    int i=1,frn1,frn2,frn3,frn4;
    
    trace(3,"decode_glostr:\n");
    
    /* frame 1 */
    frn1        =getbitu(buff,i, 4);           i+= 4+2;
    P1          =getbitu(buff,i, 2);           i+= 2;
    tk_h        =getbitu(buff,i, 5);           i+= 5;
    tk_m        =getbitu(buff,i, 6);           i+= 6;
    tk_s        =getbitu(buff,i, 1)*30;        i+= 1;
    geph->vel[0]=getbitg(buff,i,24)*P2_20*1E3; i+=24;
    geph->acc[0]=getbitg(buff,i, 5)*P2_30*1E3; i+= 5;
    geph->pos[0]=getbitg(buff,i,27)*P2_11*1E3; i+=27+4;
    
    /* frame 2 */
    frn2        =getbitu(buff,i, 4);           i+= 4;
    geph->svh   =getbitu(buff,i, 3);           i+= 3;
    P2          =getbitu(buff,i, 1);           i+= 1;
    tb          =getbitu(buff,i, 7);           i+= 7+5;
    geph->vel[1]=getbitg(buff,i,24)*P2_20*1E3; i+=24;
    geph->acc[1]=getbitg(buff,i, 5)*P2_30*1E3; i+= 5;
    geph->pos[1]=getbitg(buff,i,27)*P2_11*1E3; i+=27+4;
    
    /* frame 3 */
    frn3        =getbitu(buff,i, 4);           i+= 4;
    P3          =getbitu(buff,i, 1);           i+= 1;
    geph->gamn  =getbitg(buff,i,11)*P2_40;     i+=11+1;
    P           =getbitu(buff,i, 2);           i+= 2;
    ln          =getbitu(buff,i, 1);           i+= 1;
    geph->vel[2]=getbitg(buff,i,24)*P2_20*1E3; i+=24;
    geph->acc[2]=getbitg(buff,i, 5)*P2_30*1E3; i+= 5;
    geph->pos[2]=getbitg(buff,i,27)*P2_11*1E3; i+=27+4;
    
    /* frame 4 */
    frn4        =getbitu(buff,i, 4);           i+= 4;
    geph->taun  =getbitg(buff,i,22)*P2_30;     i+=22;
    geph->dtaun =getbitg(buff,i, 5)*P2_30;     i+= 5;
    geph->age   =getbitu(buff,i, 5);           i+= 5+14;
    P4          =getbitu(buff,i, 1);           i+= 1;
    geph->sva   =getbitu(buff,i, 4);           i+= 4+3;
    NT          =getbitu(buff,i,11);           i+=11;
    slot        =getbitu(buff,i, 5);           i+= 5;
    M           =getbitu(buff,i, 2);
    
    if (frn1!=1||frn2!=2||frn3!=3||frn4!=4) {
        trace(3,"decode_glostr error: frn=%d %d %d %d %d\n",frn1,frn2,frn3,frn4);
        return 0;
    }
    if (!(geph->sat=satno(SYS_GLO,slot))) {
        trace(2,"decode_glostr error: slot=%d\n",slot);
        return 0;
    }
    geph->frq=0;
    geph->iode=tb;
    tow=time2gpst(gpst2utc(geph->tof),&week);
    tod=fmod(tow,86400.0); tow-=tod;
    tof=tk_h*3600.0+tk_m*60.0+tk_s-10800.0; /* lt->utc */
    if      (tof<tod-43200.0) tof+=86400.0;
    else if (tof>tod+43200.0) tof-=86400.0;
    geph->tof=utc2gpst(gpst2time(week,tow+tof));
    toe=tb*900.0-10800.0; /* lt->utc */
    if      (toe<tod-43200.0) toe+=86400.0;
    else if (toe>tod+43200.0) toe-=86400.0;
    geph->toe=utc2gpst(gpst2time(week,tow+toe)); /* utc->gpst */
    return 1;
}
/* decode gps/qzss navigation data subframe 1 --------------------------------*/
static int decode_subfrm1(const unsigned char *buff, eph_t *eph)
{
    double tow,toc;
    int i=48,week,iodc0,iodc1,tgd;
    
    trace(4,"decode_subfrm1:\n");
    trace(5,"decode_subfrm1: buff="); traceb(5,buff,30);
    
    tow        =getbitu(buff,24,17)*6.0;           /* transmission time */
    week       =getbitu(buff,i,10);       i+=10;
    eph->code  =getbitu(buff,i, 2);       i+= 2;
    eph->sva   =getbitu(buff,i, 4);       i+= 4;   /* ura index */
    eph->svh   =getbitu(buff,i, 6);       i+= 6;
    iodc0      =getbitu(buff,i, 2);       i+= 2;
    eph->flag  =getbitu(buff,i, 1);       i+= 1+87;
    tgd        =getbits(buff,i, 8);       i+= 8;
    iodc1      =getbitu(buff,i, 8);       i+= 8;
    toc        =getbitu(buff,i,16)*16.0;  i+=16;
    eph->f2    =getbits(buff,i, 8)*P2_55; i+= 8;
    eph->f1    =getbits(buff,i,16)*P2_43; i+=16;
    eph->f0    =getbits(buff,i,22)*P2_31;
    
    eph->tgd[0]=tgd==-128?0.0:tgd*P2_31; /* ref [4] */
    eph->iodc=(iodc0<<8)+iodc1;
    eph->week=adjgpsweek(week); /* week of tow */
    eph->ttr=gpst2time(eph->week,tow);
    eph->toc=gpst2time(eph->week,toc);
    
    return 1;
}
/* decode gps/qzss navigation data subframe 2 --------------------------------*/
static int decode_subfrm2(const unsigned char *buff, eph_t *eph)
{
    double sqrtA;
    int i=48;
    
    trace(4,"decode_subfrm2:\n");
    trace(5,"decode_subfrm2: buff="); traceb(5,buff,30);
    
    eph->iode=getbitu(buff,i, 8);              i+= 8;
    eph->crs =getbits(buff,i,16)*P2_5;         i+=16;
    eph->deln=getbits(buff,i,16)*P2_43*SC2RAD; i+=16;
    eph->M0  =getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->cuc =getbits(buff,i,16)*P2_29;        i+=16;
    eph->e   =getbitu(buff,i,32)*P2_33;        i+=32;
    eph->cus =getbits(buff,i,16)*P2_29;        i+=16;
    sqrtA    =getbitu(buff,i,32)*P2_19;        i+=32;
    eph->toes=getbitu(buff,i,16)*16.0;         i+=16;
    eph->fit =getbitu(buff,i, 1)?0.0:4.0; /* 0:4hr,1:>4hr */
    
    eph->A=sqrtA*sqrtA;
    
    return 2;
}
/* decode gps/qzss navigation data subframe 3 --------------------------------*/
static int decode_subfrm3(const unsigned char *buff, eph_t *eph)
{
    double tow,toc;
    int i=48,iode;
    
    trace(4,"decode_subfrm3:\n");
    trace(5,"decode_subfrm3: buff="); traceb(5,buff,30);
    
    eph->cic =getbits(buff,i,16)*P2_29;        i+=16;
    eph->OMG0=getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->cis =getbits(buff,i,16)*P2_29;        i+=16;
    eph->i0  =getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->crc =getbits(buff,i,16)*P2_5;         i+=16;
    eph->omg =getbits(buff,i,32)*P2_31*SC2RAD; i+=32;
    eph->OMGd=getbits(buff,i,24)*P2_43*SC2RAD; i+=24;
    iode     =getbitu(buff,i, 8);              i+= 8;
    eph->idot=getbits(buff,i,14)*P2_43*SC2RAD;
    
    /* check iode and iodc consistency */
    if (iode!=eph->iode||iode!=(eph->iodc&0xFF)) return 0;
    
    /* adjustment for week handover */
    tow=time2gpst(eph->ttr,&eph->week);
    toc=time2gpst(eph->toc,NULL);
    if      (eph->toes<tow-302400.0) {eph->week++; tow-=604800.0;}
    else if (eph->toes>tow+302400.0) {eph->week--; tow+=604800.0;}
    eph->toe=gpst2time(eph->week,eph->toes);
    eph->toc=gpst2time(eph->week,toc);
    eph->ttr=gpst2time(eph->week,tow);
    
    return 3;
}
/* decode gps/qzss almanac ---------------------------------------------------*/
static void decode_almanac(const unsigned char *buff, int sat, alm_t *alm)
{
    gtime_t toa;
    double deltai,sqrtA,tt;
    int i=50,f0;
    
    trace(4,"decode_almanac: sat=%2d\n",sat);
    
    if (!alm||alm[sat-1].week==0) return;
    
    alm[sat-1].sat =sat;
    alm[sat-1].e   =getbits(buff,i,16)*P2_21;        i+=16;
    alm[sat-1].toas=getbitu(buff,i, 8)*4096.0;       i+= 8;
    deltai         =getbits(buff,i,16)*P2_19*SC2RAD; i+=16;
    alm[sat-1].OMGd=getbits(buff,i,16)*P2_38*SC2RAD; i+=16;
    alm[sat-1].svh =getbitu(buff,i, 8);              i+= 8;
    sqrtA          =getbitu(buff,i,24)*P2_11;        i+=24;
    alm[sat-1].OMG0=getbits(buff,i,24)*P2_23*SC2RAD; i+=24;
    alm[sat-1].omg =getbits(buff,i,24)*P2_23*SC2RAD; i+=24;
    alm[sat-1].M0  =getbits(buff,i,24)*P2_23*SC2RAD; i+=24;
    f0             =getbitu(buff,i, 8);              i+= 8;
    alm[sat-1].f1  =getbits(buff,i,11)*P2_38;        i+=11;
    alm[sat-1].f0  =getbits(buff,i, 3)*P2_17+f0*P2_20;
    alm[sat-1].A   =sqrtA*sqrtA;
    alm[sat-1].i0  =0.3*SC2RAD+deltai;
    
    toa=gpst2time(alm[sat-1].week,alm[sat-1].toas);
    tt=timediff(toa,alm[sat-1].toa);
    if      (tt<302400.0) alm[sat-1].week--;
    else if (tt>302400.0) alm[sat-1].week++;
    alm[sat-1].toa=gpst2time(alm[sat-1].week,alm[sat-1].toas);
}
/* decode gps navigation data subframe 4 -------------------------------------*/
static void decode_gps_subfrm4(const unsigned char *buff, alm_t *alm,
                               double *ion, double *utc, int *leaps)
{
    int i,sat,svid=getbitu(buff,50,6);
    
    if (25<=svid&&svid<=32) { /* page 2,3,4,5,7,8,9,10 */
        
        /* decode almanac */
        sat=getbitu(buff,50,6);
        if (1<=sat&&sat<=32) decode_almanac(buff,sat,alm);
    }
    else if (svid==63) { /* page 25 */
        
        /* decode as and sv config */
        i=56;
        for (sat=1;sat<=32;sat++) {
            if (alm) alm[sat-1].svconf=getbitu(buff,i,4);
            i+=4;
        }
        /* decode sv health */
        i=186;
        for (sat=25;sat<=32;sat++) {
            if (alm) alm[sat-1].svh   =getbitu(buff,i,6);
            i+=6;
        }
    }
    else if (svid==56) { /* page 18 */
        
        /* decode ion/utc parameters */
        if (ion) {
            i=56;
            ion[0]=getbits(buff,i, 8)*P2_30;     i+= 8;
            ion[1]=getbits(buff,i, 8)*P2_27;     i+= 8;
            ion[2]=getbits(buff,i, 8)*P2_24;     i+= 8;
            ion[3]=getbits(buff,i, 8)*P2_24;     i+= 8;
            ion[4]=getbits(buff,i, 8)*pow(2,11); i+= 8;
            ion[5]=getbits(buff,i, 8)*pow(2,14); i+= 8;
            ion[6]=getbits(buff,i, 8)*pow(2,16); i+= 8;
            ion[7]=getbits(buff,i, 8)*pow(2,16);
        }
        if (utc) {
            i=120;
            utc[1]=getbits(buff,i,24)*P2_50;     i+=24;
            utc[0]=getbits(buff,i,32)*P2_30;     i+=32;
            utc[2]=getbits(buff,i, 8)*pow(2,12); i+= 8;
            utc[3]=getbitu(buff,i, 8);
        }
        if (leaps) {
            i=192;
            *leaps=getbits(buff,i,8);
        }
    }
}
/* decode gps navigation data subframe 5 -------------------------------------*/
static void decode_gps_subfrm5(const unsigned char *buff, alm_t *alm)
{
    double toas;
    int i,sat,week,svid=getbitu(buff,50,6);
    
    if (1<=svid&&svid<=24) { /* page 1-24 */
        
        /* decode almanac */
        sat=getbitu(buff,50,6);
        if (1<=sat&&sat<=32) decode_almanac(buff,sat,alm);
    }
    else if (svid==51) { /* page 25 */
        
        if (alm) {
            i=56;
            toas=getbitu(buff,i,8)*4096; i+=8;
            week=getbitu(buff,i,8);      i+=8;
            week=adjgpsweek(week);
            
            /* decode sv health */
            for (sat=1;sat<=24;sat++) {
                alm[sat-1].svh=getbitu(buff,i,6); i+=6;
            }
            for (sat=1;sat<=32;sat++) {
                alm[sat-1].toas=toas;
                alm[sat-1].week=week;
                alm[sat-1].toa=gpst2time(week,toas);
            }
        }
    }
}
/* decode qzss navigation data subframe 4/5 ----------------------------------*/
static void decode_qzs_subfrm45(const unsigned char *buff, alm_t *alm,
                                double *ion, double *utc, int *leaps)
{
    int i,j,sat,toas,week,svid=getbitu(buff,50,6);
    
    if (1<=svid&&svid<=5) { /* qzss almanac */
        
        if (!(sat=satno(SYS_QZS,192+svid))) return;
        decode_almanac(buff,sat,alm);
    }
    else if (svid==51) { /* qzss health */
        
        if (alm) {
            i=56;
            toas=getbitu(buff,i,8)*4096; i+=8;
            week=getbitu(buff,i,8);      i+=8;
            week=adjgpsweek(week);
            
            for (j=0;j<5;j++) {
                if (!(sat=satno(SYS_QZS,193+j))) continue;
                alm[sat-1].toas=toas;
                alm[sat-1].week=week;
                alm[sat-1].toa=gpst2time(week,toas);
                alm[sat-1].svh=getbitu(buff,i,6); i+=6;
            }
        }
    }
    else if (svid==56) { /* ion/utc parameters */
        
        if (ion) {
            i=56;
            ion[0]=getbits(buff,i, 8)*P2_30;     i+= 8;
            ion[1]=getbits(buff,i, 8)*P2_27;     i+= 8;
            ion[2]=getbits(buff,i, 8)*P2_24;     i+= 8;
            ion[3]=getbits(buff,i, 8)*P2_24;     i+= 8;
            ion[4]=getbits(buff,i, 8)*pow(2,11); i+= 8;
            ion[5]=getbits(buff,i, 8)*pow(2,14); i+= 8;
            ion[6]=getbits(buff,i, 8)*pow(2,16); i+= 8;
            ion[7]=getbits(buff,i, 8)*pow(2,16);
        }
        if (utc) {
            i=120;
            utc[1]=getbits(buff,i,24)*P2_50;     i+=24;
            utc[0]=getbits(buff,i,32)*P2_30;     i+=32;
            utc[2]=getbits(buff,i, 8)*pow(2,12); i+= 8;
            utc[3]=getbitu(buff,i, 8);
        }
    }
}
/* decode gps/qzss navigation data subframe 4 --------------------------------*/
static int decode_subfrm4(const unsigned char *buff, alm_t *alm, double *ion,
                          double *utc, int *leaps)
{
    int dataid=getbitu(buff,48,2);
    
    trace(4,"decode_subfrm4: dataid=%d\n",dataid);
    trace(5,"decode_subfrm4: buff="); traceb(5,buff,30);
    
    if (dataid==1) { /* gps */
        decode_gps_subfrm4(buff,alm,ion,utc,leaps);
    }
    else if (dataid==3) { /* qzss */
        decode_qzs_subfrm45(buff,alm,ion,utc,leaps);
    }
    return 4;
}
/* decode gps/qzss navigation data subframe 5 --------------------------------*/
static int decode_subfrm5(const unsigned char *buff, alm_t *alm, double *ion,
                          double *utc, int *leaps)
{
    int dataid=getbitu(buff,48,2);
    
    trace(4,"decode_subfrm5: dataid=%d\n",dataid);
    trace(5,"decode_subfrm5: buff="); traceb(5,buff,30);
    
    if (dataid==1) { /* gps */
        decode_gps_subfrm5(buff,alm);
    }
    else if (dataid==3) { /* qzss */
        decode_qzs_subfrm45(buff,alm,ion,utc,leaps);
    }
    return 5;
}
/* decode gps/qzss navigation data frame ---------------------------------------
* decode navigation data frame and extract ephemeris and ion/utc parameters
* args   : unsigned char *buff I gps navigation data frame (without parity)
*                                  buff[0-29]: 24 bits x 10 words
*          eph_t *eph    IO     ephemeris message      (NULL: no input)
*          alm_t *alm    IO     almanac                (NULL: no input)
*          double *ion   IO     ionospheric parameters (NULL: no input)
*          double *utc   IO     delta-utc parameters   (NULL: no input)
*          int   *leaps  IO     leap seconds (s)       (NULL: no input)
* return : status (0:no valid, 1-5:subframe id)
* notes  : use cpu time to resolve modulo 1024 ambiguity of the week number
*          see ref [1]
*          utc[3] reference week for utc parameter is truncated in 8 bits
*          ion and utc parameters by qzss indicate local iono and qzst-utc
*          parameters.
*-----------------------------------------------------------------------------*/
extern int decode_frame(const unsigned char *buff, eph_t *eph, alm_t *alm,
                        double *ion, double *utc, int *leaps)
{
    int id=getbitu(buff,43,3); /* subframe id */
    
    trace(3,"decodefrm: id=%d\n",id);
    
    switch (id) {
        case 1: return decode_subfrm1(buff,eph);
        case 2: return decode_subfrm2(buff,eph);
        case 3: return decode_subfrm3(buff,eph);
        case 4: return decode_subfrm4(buff,alm,ion,utc,leaps);
        case 5: return decode_subfrm5(buff,alm,ion,utc,leaps);
    }
    return 0;
}
/* initialize receiver raw data control ----------------------------------------
* initialize receiver raw data control struct and reallocate obsevation and
* epheris buffer
* args   : raw_t  *raw   IO     receiver raw data control struct
* return : status (1:ok,0:memory allocation error)
*-----------------------------------------------------------------------------*/
extern int init_raw(raw_t *raw)
{
    const double lam_glo[NFREQ]={CLIGHT/FREQ1_GLO,CLIGHT/FREQ2_GLO};
    gtime_t time0={0};
    obsd_t data0={{0}};
    eph_t  eph0 ={0,-1,-1};
    alm_t  alm0 ={0,-1};
    geph_t geph0={0,-1};
    seph_t seph0={0};
    sbsmsg_t sbsmsg0={0};
    lexmsg_t lexmsg0={0};
    int i,j,sys;
    
    trace(3,"init_raw:\n");
    
    raw->time=time0;
    raw->ephsat=0;
    raw->sbsmsg=sbsmsg0;
    raw->msgtype[0]='\0';
    for (i=0;i<MAXSAT;i++) {
        for (j=0;j<380;j++) raw->subfrm[i][j]=0;
        for (j=0;j<NFREQ+NEXOBS;j++) {
            raw->tobs [i][j]=time0;
            raw->lockt[i][j]=0.0;
            raw->halfc[i][j]=0;
        }
        raw->icpp[i]=raw->off[i]=raw->prCA[i]=raw->dpCA[i]=0.0;
    }
    for (i=0;i<MAXOBS;i++) raw->freqn[i]=0;
    raw->lexmsg=lexmsg0;
    raw->icpc=0.0;
    raw->nbyte=raw->len=0;
    raw->iod=raw->flag=raw->tbase=raw->outtype=0;
    raw->tod=-1;
    for (i=0;i<MAXRAWLEN;i++) raw->buff[i]=0;
    raw->opt[0]='\0';
    raw->receive_time=0.0;
    raw->plen=raw->pbyte=raw->page=raw->reply=0;
    raw->week=0;
    
    raw->obs.data =NULL;
    raw->obuf.data=NULL;
    raw->nav.eph  =NULL;
    raw->nav.alm  =NULL;
    raw->nav.geph =NULL;
    raw->nav.seph =NULL;
    
    if (!(raw->obs.data =(obsd_t *)malloc(sizeof(obsd_t)*MAXOBS))||
        !(raw->obuf.data=(obsd_t *)malloc(sizeof(obsd_t)*MAXOBS))||
        !(raw->nav.eph  =(eph_t  *)malloc(sizeof(eph_t )*MAXSAT))||
        !(raw->nav.alm  =(alm_t  *)malloc(sizeof(alm_t )*MAXSAT))||
        !(raw->nav.geph =(geph_t *)malloc(sizeof(geph_t)*NSATGLO))||
        !(raw->nav.seph =(seph_t *)malloc(sizeof(seph_t)*NSATSBS*2))) {
        free_raw(raw);
        return 0;
    }
    raw->obs.n =0;
    raw->obuf.n=0;
    raw->nav.n =MAXSAT;
    raw->nav.na=MAXSAT;
    raw->nav.ng=NSATGLO;
    raw->nav.ns=NSATSBS*2;
    for (i=0;i<MAXOBS   ;i++) raw->obs.data [i]=data0;
    for (i=0;i<MAXOBS   ;i++) raw->obuf.data[i]=data0;
    for (i=0;i<MAXSAT   ;i++) raw->nav.eph  [i]=eph0;
    for (i=0;i<MAXSAT   ;i++) raw->nav.alm  [i]=alm0;
    for (i=0;i<NSATGLO  ;i++) raw->nav.geph [i]=geph0;
    for (i=0;i<NSATSBS*2;i++) raw->nav.seph [i]=seph0;
    for (i=0;i<MAXSAT;i++) for (j=0;j<NFREQ;j++) {
        if (!(sys=satsys(i+1,NULL))) continue;
        raw->nav.lam[i][j]=sys==SYS_GLO?lam_glo[j]:lam_carr[j];
    }
    raw->sta.name[0]=raw->sta.marker[0]='\0';
    raw->sta.antdes[0]=raw->sta.antsno[0]='\0';
    raw->sta.rectype[0]=raw->sta.recver[0]=raw->sta.recsno[0]='\0';
    raw->sta.antsetup=raw->sta.itrf=raw->sta.deltype=0;
    for (i=0;i<3;i++) {
        raw->sta.pos[i]=raw->sta.del[i]=0.0;
    }
    raw->sta.hgt=0.0;
    return 1;
}
/* free receiver raw data control ----------------------------------------------
* free observation and ephemeris buffer in receiver raw data control struct
* args   : raw_t  *raw   IO     receiver raw data control struct
* return : none
*-----------------------------------------------------------------------------*/
extern void free_raw(raw_t *raw)
{
    trace(3,"free_raw:\n");
    
    free(raw->obs.data ); raw->obs.data =NULL; raw->obs.n =0;
    free(raw->obuf.data); raw->obuf.data=NULL; raw->obuf.n=0;
    free(raw->nav.eph  ); raw->nav.eph  =NULL; raw->nav.n =0;
    free(raw->nav.alm  ); raw->nav.alm  =NULL; raw->nav.na=0;
    free(raw->nav.geph ); raw->nav.geph =NULL; raw->nav.ng=0;
    free(raw->nav.seph ); raw->nav.seph =NULL; raw->nav.ns=0;
}
/* input receiver raw data from stream -----------------------------------------
* fetch next receiver raw data and input a message from stream
* args   : raw_t  *raw   IO     receiver raw data control struct
*          int    format I      receiver raw data format (STRFMT_???)
*          unsigned char data I stream data (1 byte)
* return : status (-1: error message, 0: no message, 1: input observation data,
*                  2: input ephemeris, 3: input sbas message,
*                  9: input ion/utc parameter, 31: input lex message)
*-----------------------------------------------------------------------------*/
extern int input_raw(raw_t *raw, int format, unsigned char data)
{
    trace(5,"input_raw: format=%d data=0x%02x\n",format,data);
    
    switch (format) {
        case STRFMT_OEM4 : return input_oem4 (raw,data);
        case STRFMT_OEM3 : return input_oem3 (raw,data);
        case STRFMT_UBX  : return input_ubx  (raw,data);
        case STRFMT_SS2  : return input_ss2  (raw,data);
        case STRFMT_CRES : return input_cres (raw,data);
        case STRFMT_STQ  : return input_stq  (raw,data);
        case STRFMT_GW10 : return input_gw10 (raw,data);
        case STRFMT_JAVAD: return input_javad(raw,data);
        case STRFMT_NVS  : return input_nvs  (raw,data);
        case STRFMT_BINEX: return input_bnx  (raw,data);
        case STRFMT_RT17 : return input_rt17 (raw,data);
        case STRFMT_LEXR : return input_lexr (raw,data);
    }
    return 0;
}
/* input receiver raw data from file -------------------------------------------
* fetch next receiver raw data and input a message from file
* args   : raw_t  *raw   IO     receiver raw data control struct
*          int    format I      receiver raw data format (STRFMT_???)
*          FILE   *fp    I      file pointer
* return : status(-2: end of file/format error, -1...31: same as above)
*-----------------------------------------------------------------------------*/
extern int input_rawf(raw_t *raw, int format, FILE *fp)
{
    trace(4,"input_rawf: format=%d\n",format);
    
    switch (format) {
        case STRFMT_OEM4 : return input_oem4f (raw,fp);
        case STRFMT_OEM3 : return input_oem3f (raw,fp);
        case STRFMT_UBX  : return input_ubxf  (raw,fp);
        case STRFMT_SS2  : return input_ss2f  (raw,fp);
        case STRFMT_CRES : return input_cresf (raw,fp);
        case STRFMT_STQ  : return input_stqf  (raw,fp);
        case STRFMT_GW10 : return input_gw10f (raw,fp);
        case STRFMT_JAVAD: return input_javadf(raw,fp);
        case STRFMT_NVS  : return input_nvsf  (raw,fp);
        case STRFMT_BINEX: return input_bnxf  (raw,fp);
        case STRFMT_RT17 : return input_rt17f (raw,fp);
        case STRFMT_LEXR : return input_lexrf (raw,fp);
    }
    return -2;
}
